Any PCM dealers on here?

[IDBoating]

Please call me I have the fix for this. Ben there done that. I will discuss it with you. You need to get ride of the wet seal.

I just installed the wet version at the specific recommendation of PSS. They specifically state that boats that go on plane should use the wet version. My dry version - the one that came from the factory - was doing exactly what PSS said it would do... creating an air pocket under the shaft seal that permitted it to run dry. It was scoring and damaging the carbon ring, and causing this sound when the propshaft was turning:

Click here to listen

When this happened, pulling back on the carbon ring would cause a "hissssssssss" as the air pocket was released. Then the sound would stop.

I have the original "dry" carbon ring. It is scored something terrible. Now the "wet" version is in place and I just need to plumb to it.

I got your PM, I'll call tomorrow. I am very interested in your comments but at this point the "wet" version is already installed based on PSS's specific instructions.

Talk to you tomorrow... thanks!

[IDBoating]

Just got off the phone with you. Thanks so much for the conversation. I'll keep you posted on how things proceed!

[SPBFAN]

That sounds Horrible. I know the guys and PCM and PSS well. If they say it is okay to pull from the CAT area do it. They will stand behind it.

[IDBoating]

This morning I spoke to "Eric" (I think that was his name) at PSS, the makers of the shaft seal. He said using exhaust temperature water is fine, and in fact what most users do.

I reminded him that the engine is running at 160F and the water will be at least that hot coming out of the exhaust hoses. I said I was concerned that the temperature differential against the cool lake water would stress the carbon ring, perhaps even crack it. He said no, it will easily handle it. He cited the example that they sell these to the Coast Guard in Puget Sound, where the water is "REALLY cold", and said "they are running exhaust water to their shaft seals".

He also said that engine manufacturers do not want incoming cooling water routed away from the engine, which is why the engine manufacturers always recommend pulling the shaft seal water from the exhaust system. He said PSS goes along with that recommendation.

He claims to have worked at PSS for 20 years, and to now be "running" their shaft seal division, and that "it is perfectly fine" and there is "absolutely no problem" running exhaust water to the carbon ring. "The important thing is to keep water running to it."

So... I appreciate all of the comments (public and private) that I've received on this. Based on everything, and most particularly since both PCM and PSS agree on this answer, I'm going to draw water from the exhaust hoses and route it to my wet PSS shaft seal.

I'll post photos when I have them. Thanks!

[shawndoggy]

So are you just going to replace one of the drain plugs with a barbed fitting (would that even work?), or something else?

I've never looked at how mine is hooked up but will when I next go up to the boat.

[IDBoating]

So are you just going to replace one of the drain plugs with a barbed fitting (would that even work?), or something else?

No, I'm going to insert a T fitting into one of the CAT cooling hoses. Where to do this is clearly illustrated in the PCM manual, though if you talk to them on the phone you may get conflicting data once in a while. The last guy I spoke to at PCM ("Gary") stated that these hoses do indeed have pressurized water in them whenever the engine is running.

It is tempting to use a barbed fitting in a drain plug, but I am going to follow the matching recommendations from PCM and PSS and pull it from the hose.

I've never looked at how mine is hooked up but will when I next go up to the boat.

I would sincerely appreciate that. Photos would be a huge bonus!